Axiom Home Page Forums General Discussion Home Theater Other options for a rear centre speaker...

For some reason this idea popped into my head when I was dusting my speakers this morning. This fall, after I upgrade my AV receiver, I plan to go to a 6.1 set-up. My HT room is 13 feet across, and I think that a 7.1 set-up may be a waste. I couldn't be happier with my QS8's, and just assumed that I'd simply buy another one. However it suddenly occurred to me that maybe having a more directed speaker might be better for movies. What would you guys think of using something like a VP100 for the rear centre?

I think that there's an issue with using a direct radiator for a rear center. I have heard that if you do that, the sound behind you sounds like it's in front of you. Something about psychoacoustics.

Keep the idea of another QS8, I have 3 across the back and the sound is even more enveloping. I have played with a direct radiating in the rear center(not Axiom) and the sound was very direct and seemed not as smooth? for certain surround effects. You will be extremely happy with a third QS8 trust me.

Bayne, it isn't clear why a 13' width would be a factor. The back surround speakers should be separated so that they're outside the listening position to each side, and once that exists a rule-of-thumb is to separate them about as much as they're behind the listeners. Using surround modes such as DPLIIx or Logic 7 sends different "stereo" surround material to each back speaker.

I was looking at THX's website last night, and I was surprised that their speaker layout recommendation for 7.1 has the two rear channels side-by-side on the back wall.

http://thx.com/home/setup/speakers/71.html

What's the point of having two channels back there if there's no space between them?

I was looking at the user manual for a Pioneer receiver that has the THX mode and this spacing is also what they recommend. However, the receiver does allow you to set the distance between the rear speakers as well.

It also states that the SBL and SBR should be direct firing. Weird? Why then would you even bother setting up 7.1 like this when you could save some money and just go with one rear speaker? For my money, one QS8 would probably worker better at created a more enveloping sound field than 2 direct firing speakers.

This may be of interest.

What a gorgeous day, eh? More beer and BBQing tonight for sure.

The THX literature doesn't make entirely clear(surprise)the point that the setup with the rear speakers together is only effective when used with their proprietary ASA(Advanced Speaker Array)processing, which is an option on THX certified receivers. It's said to apply special surround processing so that both a solid rear field and left/right directionality can be heard, despite the lack of speaker separation. This isn't available to me and there have been some with THX available who've reported that they preferred a setup with separated back speakers, which is what is generally required. As was mentioned above, processing such as DPLIIx can provide separate left and right rear signals, which is one of the reasons for using two back surrounds, if possible.